The present invention relates to the art of manufacturing chairs and, more particularly, to a novel locking assembly for rocking chairs. The locking assembly is characterized by its ability to lock the body portion of the chair relative to the base portion of the chair in a selected position.
A typical rocking chair includes a body supporting structure that is mounted on a chair base by a rocking assembly. The prior art has recognised that it is desirable to provide rocking chairs with a locking mechanism that allows retaining the body-supporting portion of the chair in a certain position with relation to the base. This is useful in instances where the occupant of the chair wishes to negate at least temporarily the rocking function of the chair.
One locking mechanism that is known in the art comprises two components, namely a rack element including a plurality of fingers in a spaced apart relationship, and a pin element that can fit between selected fingers of the rack. The rack element is mounted to the body-supporting portion of the chair while the pin is mounted to the chair base portion. The rack element is also provided with a linkage that allows moving the rack in and out of engagement with the pin. In use, when the occupant of the chair desires to lock the chair in a certain position, he or she operates the linkage to bring the rack in engagement with the pin such that the pin enters the fingers that correspond to the selected position in which the chair is to be immobilized. To release the lock, it suffices to operate the linkage in the opposite direction and thus disengage the rack from the pin.
This type of locking mechanism is not entirely satisfactory for a number of reasons. One of its drawbacks relates to the smoothness of operation. For instance, the rack will engage with the pin only when the inter-pin space is precisely aligned with the pin. In a situation when the occupant of the chair attempts to engage the locking mechanism in a position such that a finger of the rack interferes with the pin, engagement will not be possible until the occupant of the chair slightly shifts the position of the body-supporting portion of the chair such that the pin enters between two fingers of the rack.
Another drawback is the requirement of providing a long rack when a wide range of locking positions on the chair are desirable, which may not be aesthetically advantageous.
Against this background, it clearly appears that there is a need in the industry to provide a locking assembly for rocking chairs that avoids or at least alleviates drawbacks associated with prior art locking assemblies.
In one aspect the present invention provides a locking assembly for a rocking chair, the rocking chair having a body-supporting portion mounted for rocking movement on a chair base portion. The locking assembly comprises a first locking assembly component for mounting to the body-supporting portion and a second locking assembly component for mounting to the chair base portion. The first and the second locking assembly components can be interlocked to retain the body-supporting portion at a selected position relative to the chair base portion.
The first locking assembly component includes a pair of jaws capable to acquire two operative conditions. The second locking assembly component includes at least one pin. In the first operative condition, the jaws wedge the pin between them and thus retain the body-supporting portion of the chair relative to the base portion of the chair in a certain position, preventing the body-supporting portion of the chair from rocking. In the second operative position, the jaws release the pin, allowing the pin to move relative to the jaws such as to allow the chair to rock.
An advantage of the locking mechanism over prior art designs is its smoothness of operation. As the first locking assembly component is operated to cause the pin to become wedged between the jaws, the jaws and consequently the body-supporting portion of the chair, are guided toward the locking position when the jaws engage the pin. There is no necessity for the occupant of the chair to gage and adjust the position of the body-supporting portion of the chair relative to the chair base portion such as to allow the two components of the locking assembly to interengage. Another advantage of this locking assembly is its low profile. To extend the range of locking positions, it suffices to add more pins to the chair base, where each pin corresponds to a different locking position. Since the pins are relatively small, the locking mechanism remains discreet.
One possible variant of the structure described above is to reverse the position of the locking assembly components, and mount the first locking assembly component to the chair base portion while mounting the second locking assembly component to the body-supporting portion of the chair.
In a specific non-limiting example of implementation, the first locking assembly component includes a pair of jaws that move with relation to one another when a linkage is operated. Typically, the linkage includes a handle that extends on the side of the chair and that can be operated by the user to open or to close the jaws. The relationship between the jaws is such that when a movement is imparted to one jaw by the linkage, the other jaw is also caused to move. When the linkage is operated to engage the locking assembly, the jaws move with relation to one another such as to grip the pin. In particular, the gripping faces of the jaws undergo motions in two directions. First, the gripping faces move away from one another such as to define a receptacle for receiving the pin. Second, the gripping faces move down to come and bear on the pin, thus immobilizing it. The arrangement between the various parts forming the gripping assembly is such that during the initial phase of the locking assembly engagement, the gripping faces of the jaws move faster away from one another than toward the pin. This arrangements allows to first form the pin catching receptacle and then to cause the receptacle to fit on the pin such as to wedge the pin. When the locking assembly is released, the opposite sequence of motions occurs.
The present invention also extends to a rocking chair including the locking assembly described above.
In another broad aspect, the invention provides a chair with a body-supporting portion that moves relative to a chair base portion. The body-supporting portion has a backrest and a seat. A locking assembly is provided to prevent the movement of the body-supporting portion relative to the chair base portion. The chair has a linkage to operate the locking assembly. The linkage includes a resilient strip mounted on the backrest. When an occupant applies pressure on the backrest the strip is deformed rearwardly. When the pressure ceases, the strip returns to its original position. The linkage is coupled to the locking assembly to cause the locking assembly to operate and prevent the movement of the body-supporting portion when the strip is in its original position. Conversely, when the strip is deformed rearwardly, the locking assembly is disengaged.